Enable suspending clk scaling on no request for Qualcomm SoC.
Signed-off-by: Ram Prakash Gupta <quic_rampraka@quicinc.com>
Link: https://lore.kernel.org/r/20240627083756.25340-3-quic_rampraka@quicinc.com
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Currently UFS clk scaling is getting suspended only when the clks are
scaled down. When high load is generated, a huge amount of latency is added
due to scaling up the clk and completing the request post that.
Suspending the scaling in its existing state when high load is generated
improves the random performance KPI by 28%. So suspending the scaling when
there are no requests. And the clk would be put in low scaled state when
the actual request load is low.
Make this change optional by having the check enabled using vops since for
some devices suspending without bringing the clk in low scaled state might
have impact on power consumption of the SoC.
Signed-off-by: Ram Prakash Gupta <quic_rampraka@quicinc.com>
Link: https://lore.kernel.org/r/20240627083756.25340-2-quic_rampraka@quicinc.com
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The test for a possible shift overflow is not correct. Fix it by replacing
the '>' with a '>='.
Signed-off-by: Tomas Henzl <thenzl@redhat.com>
Link: https://lore.kernel.org/r/20240627074827.13672-1-thenzl@redhat.com
Suggested-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The 'phy' parameter supplied to lan9303_phy_read/_write was sometimes a
DSA port number and sometimes a PHY address. This isn't a problem as
long as they are equal. But if the external phy_addr_sel_strap pin is
wired to 'high', the PHY addresses change from 0-1-2 to 1-2-3 (CPU,
slave0, slave1). In this case, lan9303_phy_read/_write must translate
between DSA port numbers and the corresponding PHY address.
Fixes: a1292595e0 ("net: dsa: add new DSA switch driver for the SMSC-LAN9303")
Signed-off-by: Christian Eggers <ceggers@arri.de>
Reviewed-by: Michal Kubiak <michal.kubiak@intel.com>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Link: https://patch.msgid.link/20240703145718.19951-1-ceggers@arri.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Convention is DT schemas should define all properties at the top-level
and not inside of if/then schemas. That minimizes the if/then schemas
and is more future proof.
Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Serge Semin <fancer.lancer@gmail.com>
Link: https://patch.msgid.link/20240703195827.1670594-2-robh@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
In rtw89_sta_info_get_iter() 'status->he_gi' is compared to array size.
But then 'rate->he_gi' is used as array index instead of 'status->he_gi'.
This can lead to go beyond array boundaries in case of 'rate->he_gi' is
not equal to 'status->he_gi' and is bigger than array size. Looks like
"copy-paste" mistake.
Fix this mistake by replacing 'rate->he_gi' with 'status->he_gi'.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Fixes: e3ec7017f6 ("rtw89: add Realtek 802.11ax driver")
Signed-off-by: Aleksandr Mishin <amishin@t-argos.ru>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Link: https://patch.msgid.link/20240703210510.11089-1-amishin@t-argos.ru
Change 'defult' to 'default' in comments in several rtlwifi drivers.
Signed-off-by: Fredrik Lönnegren <fredrik@frelon.se>
Acked-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Link: https://patch.msgid.link/20240703070627.135328-1-fredrik@frelon.se
Driver will notify FW the target index of RFK table to use at some
moments. When MCC (multi-channel concurrent), the correctness of the
notification is especially important.
We now unify the selection logic of RFK table as below among chips.
1. check each table if it matches target channel
2. check all tables if any is idle by iterating active channels
3. replace the first table if all are busy unexpectedly
Signed-off-by: Zong-Zhe Yang <kevin_yang@realtek.com>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Link: https://patch.msgid.link/20240702124452.18747-2-pkshih@realtek.com
The C standard is vague about the signedness of enums, but in this case
here, they are treated as unsigned so the error handling does not work.
Use an int type to fix this.
Fixes: c6ed48ef52 ("power: supply: add ChromeOS EC based charge control driver")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Acked-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://lore.kernel.org/r/ZoWKEs4mCqeLyTOB@stanley.mountain
Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
MRC (multi-role concurrency) has a C2H event for status report. Newer
FW will report some kinds of failures. We parse them now and show by
debug log.
Signed-off-by: Zong-Zhe Yang <kevin_yang@realtek.com>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Link: https://patch.msgid.link/20240702124452.18747-1-pkshih@realtek.com
The BT coexistence part of 8852B and 8852BT are similar, so move shared
code into common module.
Don't change logic for existing RTL8852BE.
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Link: https://patch.msgid.link/20240701014619.7300-1-pkshih@realtek.com
Right now it's possible to hit NULL pointer dereference in
rtw_rx_fill_rx_status on hw object and/or its fields because
initialization routine can start getting USB replies before
rtw_dev is fully setup.
The stack trace looks like this:
rtw_rx_fill_rx_status
rtw8821c_query_rx_desc
rtw_usb_rx_handler
...
queue_work
rtw_usb_read_port_complete
...
usb_submit_urb
rtw_usb_rx_resubmit
rtw_usb_init_rx
rtw_usb_probe
So while we do the async stuff rtw_usb_probe continues and calls
rtw_register_hw, which does all kinds of initialization (e.g.
via ieee80211_register_hw) that rtw_rx_fill_rx_status relies on.
Fix this by moving the first usb_submit_urb after everything
is set up.
For me, this bug manifested as:
[ 8.893177] rtw_8821cu 1-1:1.2: band wrong, packet dropped
[ 8.910904] rtw_8821cu 1-1:1.2: hw->conf.chandef.chan NULL in rtw_rx_fill_rx_status
because I'm using Larry's backport of rtw88 driver with the NULL
checks in rtw_rx_fill_rx_status.
Link: https://lore.kernel.org/linux-wireless/CA+shoWQ7P49jhQasofDcTdQhiuarPTjYEDa--NiVVx494WcuQw@mail.gmail.com/
Signed-off-by: Marcin Ślusarz <mslusarz@renau.com>
Cc: Tim K <tpkuester@gmail.com>
Cc: Ping-Ke Shih <pkshih@realtek.com>
Cc: Larry Finger <Larry.Finger@lwfinger.net>
Cc: Kalle Valo <kvalo@kernel.org>
Cc: linux-wireless@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Link: https://patch.msgid.link/20240528110246.477321-1-marcin.slusarz@gmail.com
LTC2991_T_INT_CH_NR is 4. The st->temp_en[] array has LTC2991_MAX_CHANNEL
(4) elements. Thus if "channel" is equal to LTC2991_T_INT_CH_NR then we
have read one element beyond the end of the array. Flip the conditions
around so that we check if "channel" is valid before using it as an array
index.
Fixes: 2b9ea4262a ("hwmon: Add driver for ltc2991")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://lore.kernel.org/r/Zoa9Y_UMY4_ROfhF@stanley.mountain
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Add the documentation for soft offline behaviors / costs, and what the new
enable_soft_offline sysctl is for.
[jiaqiyan@google.com: fix kerneldoc warnings]
Link: https://lkml.kernel.org/r/CACw3F52=GxTCDw-PqFh3-GDM-fo3GbhGdu0hedxYXOTT4TQSTg@mail.gmail.com
[jiaqiyan@google.com: there are more blank lines needed]
Link: https://lkml.kernel.org/r/CACw3F52_obAB742XeDRNun4BHBYtrxtbvp5NkUincXdaob0j1g@mail.gmail.com
Link: https://lkml.kernel.org/r/20240626050818.2277273-5-jiaqiyan@google.com
Signed-off-by: Jiaqi Yan <jiaqiyan@google.com>
Acked-by: Oscar Salvador <osalvador@suse.de>
Acked-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Frank van der Linden <fvdl@google.com>
Cc: Jane Chu <jane.chu@oracle.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Lance Yang <ioworker0@gmail.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Add regression and new tests when hugepage has correctable memory errors,
and how userspace wants to deal with it:
* if enable_soft_offline=1, mapped hugepage is soft offlined
* if enable_soft_offline=0, mapped hugepage is intact
Free hugepages case is not explicitly covered by the tests.
Hugepage having corrected memory errors is emulated with
MADV_SOFT_OFFLINE.
[jiaqiyan@google.com: v7]
Link: https://lkml.kernel.org/r/20240628205958.2845610-4-jiaqiyan@google.com
Link: https://lkml.kernel.org/r/20240626050818.2277273-4-jiaqiyan@google.com
Signed-off-by: Jiaqi Yan <jiaqiyan@google.com>
Acked-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Frank van der Linden <fvdl@google.com>
Cc: Jane Chu <jane.chu@oracle.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Lance Yang <ioworker0@gmail.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Correctable memory errors are very common on servers with large amount of
memory, and are corrected by ECC. Soft offline is kernel's additional
recovery handling for memory pages having (excessive) corrected memory
errors. Impacted page is migrated to a healthy page if inuse; the
original page is discarded for any future use.
The actual policy on whether (and when) to soft offline should be
maintained by userspace, especially in case of an 1G HugeTLB page.
Soft-offline dissolves the HugeTLB page, either in-use or free, into
chunks of 4K pages, reducing HugeTLB pool capacity by 1 hugepage. If
userspace has not acknowledged such behavior, it may be surprised when
later failed to mmap hugepages due to lack of hugepages. In case of a
transparent hugepage, it will be split into 4K pages as well; userspace
will stop enjoying the transparent performance.
In addition, discarding the entire 1G HugeTLB page only because of
corrected memory errors sounds very costly and kernel better not doing
under the hood. But today there are at least 2 such cases doing so:
1. when GHES driver sees both GHES_SEV_CORRECTED and
CPER_SEC_ERROR_THRESHOLD_EXCEEDED after parsing CPER.
2. RAS Correctable Errors Collector counts correctable errors per
PFN and when the counter for a PFN reaches threshold
In both cases, userspace has no control of the soft offline performed
by kernel's memory failure recovery.
This commit gives userspace the control of softofflining any page: kernel
only soft offlines raw page / transparent hugepage / HugeTLB hugepage if
userspace has agreed to. The interface to userspace is a new sysctl at
/proc/sys/vm/enable_soft_offline. By default its value is set to 1 to
preserve existing behavior in kernel. When set to 0, soft-offline (e.g.
MADV_SOFT_OFFLINE) will fail with EOPNOTSUPP.
[jiaqiyan@google.com: v7]
Link: https://lkml.kernel.org/r/20240628205958.2845610-3-jiaqiyan@google.com
Link: https://lkml.kernel.org/r/20240626050818.2277273-3-jiaqiyan@google.com
Signed-off-by: Jiaqi Yan <jiaqiyan@google.com>
Acked-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Frank van der Linden <fvdl@google.com>
Cc: Jane Chu <jane.chu@oracle.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Lance Yang <ioworker0@gmail.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "Userspace controls soft-offline pages", v6.
Correctable memory errors are very common on servers with large amount of
memory, and are corrected by ECC, but with two pain points to users:
1. Correction usually happens on the fly and adds latency overhead
2. Not-fully-proved theory states excessive correctable memory
errors can develop into uncorrectable memory error.
Soft offline is kernel's additional solution for memory pages having
(excessive) corrected memory errors. Impacted page is migrated to healthy
page if it is in use, then the original page is discarded for any future
use.
The actual policy on whether (and when) to soft offline should be
maintained by userspace, especially in case of an 1G HugeTLB page.
Soft-offline dissolves the HugeTLB page, either in-use or free, into
chunks of 4K pages, reducing HugeTLB pool capacity by 1 hugepage. If
userspace has not acknowledged such behavior, it may be surprised when
later mmap hugepages MAP_FAILED due to lack of hugepages. In case of a
transparent hugepage, it will be split into 4K pages as well; userspace
will stop enjoying the transparent performance.
In addition, discarding the entire 1G HugeTLB page only because of
corrected memory errors sounds very costly and kernel better not doing
under the hood. But today there are at least 2 such cases:
1. GHES driver sees both GHES_SEV_CORRECTED and
CPER_SEC_ERROR_THRESHOLD_EXCEEDED after parsing CPER.
2. RAS Correctable Errors Collector counts correctable errors per
PFN and when the counter for a PFN reaches threshold
In both cases, userspace has no control of the soft offline performed by
kernel's memory failure recovery.
This patch series give userspace the control of softofflining any page:
kernel only soft offlines raw page / transparent hugepage / HugeTLB
hugepage if userspace has agreed to. The interface to userspace is a new
sysctl called enable_soft_offline under /proc/sys/vm. By default
enable_soft_line is 1 to preserve existing behavior in kernel.
This patch (of 4):
Logs from soft_offline_page and soft_offline_in_use_page have different
formats than majority of the memory failure code:
"Memory failure: 0x${pfn}: ${lower_case_message}"
Convert them to the following format:
"Soft offline: 0x${pfn}: ${lower_case_message}"
No functional change in this commit.
Link: https://lkml.kernel.org/r/20240626050818.2277273-1-jiaqiyan@google.com
Link: https://lkml.kernel.org/r/20240626050818.2277273-2-jiaqiyan@google.com
Signed-off-by: Jiaqi Yan <jiaqiyan@google.com>
Acked-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Lance Yang <ioworker0@gmail.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Frank van der Linden <fvdl@google.com>
Cc: Jane Chu <jane.chu@oracle.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Currently it uses WARN_ON_ONCE() if seq_buf overflows when user reads
memory.stat, the only advantage of WARN_ON_ONCE is that the splat is so
verbose that it gets noticed. And also it panics the system if
panic_on_warn is enabled. It seems like the warning is just an over
reaction and a simple pr_warn should just achieve the similar effect.
Link: https://lkml.kernel.org/r/20240628072333.2496527-1-xiujianfeng@huawei.com
Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
Suggested-by: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Both the end of memory_stat_format() and memcg_stat_format() will call
WARN_ON_ONCE(seq_buf_has_overflowed()). However, memory_stat_format() is
the only caller of memcg_stat_format(), when memcg is on the default
hierarchy, seq_buf_has_overflowed() will be executed twice, so remove the
redundant one.
Link: https://lkml.kernel.org/r/20240626094232.2432891-1-xiujianfeng@huawei.com
Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
If CONFIG_PTE_MARKER_UFFD_WP is disabled, then we turn off three features
in userfaultfd_api (UFFD_FEATURE_WP_HUGETLBFS_SHMEM,
UFFD_FEATURE_WP_UNPOPULATED, and UFFD_FEATURE_WP_ASYNC).
Currently this test always will call uffdio_regsiter with the flag
UFFDIO_REGISTER_MODE_WP. However, the kernel ensures in vma_can_userfault
that if the feature UFFD_FEATURE_WP_HUGETLBFS_SHMEM is disabled, only
allow the VM_UFFD_WP on anonymous vmas, meaning our call to
uffdio_regsiter will fail.
We still want to be able to run the test even if we have
CONFIG_PTE_MARKER_UFFD_WP disabled, so check to see if the feature
UFFD_FEATURE_WP_HUGETLBFS_SHMEM has been turned off in the test and if so,
disable us from calling uffdio_regsiter with the flag
UFFDIO_REGISTER_MODE_WP.
Link: https://lkml.kernel.org/r/20240626130513.120193-3-audra@redhat.com
Signed-off-by: Audra Mitchell <audra@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Rafael Aquini <raquini@redhat.com>
Cc: Shaohua Li <shli@fb.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Now that we have updated userfaultfd_api to correctly return EINVAL when a
feature is requested but not available, let's fix the uffd-stress test to
only set the UFFD_FEATURE_WP_UNPOPULATED feature when the config is set.
In addition, still run the test if the CONFIG_PTE_MARKER_UFFD_WP is not
set, just dont use the corresponding UFFD_FEATURE_WP_UNPOPULATED feature.
Link: https://lkml.kernel.org/r/20240626130513.120193-2-audra@redhat.com
Signed-off-by: Audra Mitchell <audra@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rafael Aquini <raquini@redhat.com>
Cc: Shaohua Li <shli@fb.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Nowadays PF_KTHREAD is sticky and it was never protected by ->alloc_lock.
Move the PF_KTHREAD check outside of task_lock() section to make this code
more understandable.
Link: https://lkml.kernel.org/r/20240626191017.GA20031@redhat.com
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
mm_update_next_owner() checks the children / real_parent->children to
avoid the "everything else" loop in the likely case, but this won't work
if a child/sibling has a zombie leader with ->mm == NULL.
Move the for_each_thread() logic into try_to_set_owner(), if nothing else
this makes the children/siblings/everything searches more consistent.
Link: https://lkml.kernel.org/r/20240626152930.GA17936@redhat.com
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jinliang Zheng <alexjlzheng@tencent.com>
Cc: Mateusz Guzik <mjguzik@gmail.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Tycho Andersen <tandersen@netflix.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Add the new helper, try_to_set_owner(), which tries to update mm->owner
once we see c->mm == mm. This way mm_update_next_owner() doesn't need to
restart the list_for_each_entry/for_each_process loops from the very
beginning if it races with exit/exec, it can just continue.
Unlike the current code, try_to_set_owner() re-checks tsk->mm == mm before
it drops tasklist_lock, so it doesn't need get/put_task_struct().
Link: https://lkml.kernel.org/r/20240626152924.GA17933@redhat.com
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jinliang Zheng <alexjlzheng@tencent.com>
Cc: Mateusz Guzik <mjguzik@gmail.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Tycho Andersen <tandersen@netflix.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The struct task_struct's in_user_fault member is not used by the cgroup
v2's memory controller, so it can be put under the CONFIG_MEMCG_V1 config
option. To do so, mem_cgroup_enter_user_fault() and
mem_cgroup_exit_user_fault() are moved under the CONFIG_MEMCG_V1 option as
well.
Link: https://lkml.kernel.org/r/20240628210317.272856-10-roman.gushchin@linux.dev
Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The memcg_in_oom field of the struct task_struct is not used by the cgroup
v2's memory controller, so it can be happily compiled out if
CONFIG_MEMCG_V1 is not set.
Link: https://lkml.kernel.org/r/20240628210317.272856-9-roman.gushchin@linux.dev
Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Put memcg1-specific members of struct mem_cgroup_per_node under the
CONFIG_MEMCG_V1 config option.
Link: https://lkml.kernel.org/r/20240628210317.272856-8-roman.gushchin@linux.dev
Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Put memcg1-specific members of struct mem_cgroup under the CONFIG_MEMCG_V1
config option. Also group them close to the end of struct mem_cgroup just
before the dynamic per-node part.
Link: https://lkml.kernel.org/r/20240628210317.272856-7-roman.gushchin@linux.dev
Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
There are only few memcg1-specific struct mem_cgroup's members accesses
left in mm/memcontrol.c. Let's guard them with the CONFIG_MEMCG_V1 config
option.
Link: https://lkml.kernel.org/r/20240628210317.272856-6-roman.gushchin@linux.dev
Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Gather all memcg1-specific struct mem_cgroup's members initialization in a
new memcg1_memcg_init() function, defined in mm/memcontrol-v1.c.
Obviously, if CONFIG_MEMCG_V1 is not set, there is no need to initialize
these fields, so the function becomes trivial.
Link: https://lkml.kernel.org/r/20240628210317.272856-5-roman.gushchin@linux.dev
Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Put cgroup v1-specific code in mem_cgroup_print_oom_meminfo() under
CONFIG_MEMCG_V1.
Link: https://lkml.kernel.org/r/20240628210317.272856-4-roman.gushchin@linux.dev
Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Move out the legacy cgroup v1 socket memory accounting code into
mm/memcontrol-v1.c.
This commit introduces three new functions: memcg1_tcpmem_active(),
memcg1_charge_skmem() and memcg1_uncharge_skmem(), which contain all
cgroup v1-specific code and become trivial if CONFIG_MEMCG_V1 isn't set.
Note, that !!memcg->tcpmem_pressure check in
mem_cgroup_under_socket_pressure() can't be easily moved into
memcontrol-v1.h without including memcontrol-v1.h from memcontrol.h which
isn't a good idea, so it's better to just #ifdef it.
Link: https://lkml.kernel.org/r/20240628210317.272856-3-roman.gushchin@linux.dev
Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "mm: memcg: put cgroup v1-specific memcg data under
CONFIG_MEMCG_V1".
This patchset puts all cgroup v1's members of struct mem_cgroup, struct
mem_cgroup_per_node and struct task_struct under the CONFIG_MEMCG_V1
config option. If cgroup v1 support is not required (and it's true for
many cgroup users these days), it allows to save a bit of memory and
compile out some code, some of which is on relatively hot paths. It also
structures the code a bit better by grouping cgroup v1-specific stuff in
one place.
This patch (of 9):
memcg_account_kmem() consists of a trivial statistics change via
mod_memcg_state() call and a relatively large memcg1-specific part.
Let's factor out the mod_memcg_state() call and move the rest into the
mm/memcontrol-v1.c file. Also rename memcg_account_kmem() into
memcg1_account_kmem() for consistency.
Link: https://lkml.kernel.org/r/20240628210317.272856-1-roman.gushchin@linux.dev
Link: https://lkml.kernel.org/r/20240628210317.272856-2-roman.gushchin@linux.dev
Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Allow proactive reclaimers to submit an additional swappiness=<val>
argument to memory.reclaim. This overrides the global or per-memcg
swappiness setting for that reclaim attempt.
For example:
echo "2M swappiness=0" > /sys/fs/cgroup/memory.reclaim
will perform reclaim on the rootcg with a swappiness setting of 0 (no
swap) regardless of the vm.swappiness sysctl setting.
Userspace proactive reclaimers use the memory.reclaim interface to trigger
reclaim. The memory.reclaim interface does not allow for any way to
effect the balance of file vs anon during proactive reclaim. The only
approach is to adjust the vm.swappiness setting. However, there are a few
reasons we look to control the balance of file vs anon during proactive
reclaim, separately from reactive reclaim:
* Swapout should be limited to manage SSD write endurance. In near-OOM
situations we are fine with lots of swap-out to avoid OOMs. As these
are typically rare events, they have relatively little impact on write
endurance. However, proactive reclaim runs continuously and so its
impact on SSD write endurance is more significant. Therefore it is
desireable to control swap-out for proactive reclaim separately from
reactive reclaim
* Some userspace OOM killers like systemd-oomd[1] support OOM killing on
swap exhaustion. This makes sense if the swap exhaustion is triggered
due to reactive reclaim but less so if it is triggered due to proactive
reclaim (e.g. one could see OOMs when free memory is ample but anon is
just particularly cold). Therefore, it's desireable to have proactive
reclaim reduce or stop swap-out before the threshold at which OOM
killing occurs.
In the case of Meta's Senpai proactive reclaimer, we adjust vm.swappiness
before writes to memory.reclaim[2]. This has been in production for
nearly two years and has addressed our needs to control proactive vs
reactive reclaim behavior but is still not ideal for a number of reasons:
* vm.swappiness is a global setting, adjusting it can race/interfere
with other system administration that wishes to control vm.swappiness.
In our case, we need to disable Senpai before adjusting vm.swappiness.
* vm.swappiness is stateful - so a crash or restart of Senpai can leave
a misconfigured setting. This requires some additional management to
record the "desired" setting and ensure Senpai always adjusts to it.
With this patch, we avoid these downsides of adjusting vm.swappiness
globally.
[1]https://www.freedesktop.org/software/systemd/man/latest/systemd-oomd.service.html
[2]https://github.com/facebookincubator/oomd/blob/main/src/oomd/plugins/Senpai.cpp#L585-L598
Link: https://lkml.kernel.org/r/20240103164841.2800183-3-schatzberg.dan@gmail.com
Signed-off-by: Dan Schatzberg <schatzberg.dan@gmail.com>
Suggested-by: Yosry Ahmed <yosryahmed@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Chris Li <chrisl@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Yue Zhao <findns94@gmail.com>
Cc: Zefan Li <lizefan.x@bytedance.com>
Cc: Nhat Pham <nphamcs@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "Add swappiness argument to memory.reclaim", v6.
This patch proposes augmenting the memory.reclaim interface with a
swappiness=<val> argument that overrides the swappiness value for that
instance of proactive reclaim.
Userspace proactive reclaimers use the memory.reclaim interface to trigger
reclaim. The memory.reclaim interface does not allow for any way to
effect the balance of file vs anon during proactive reclaim. The only
approach is to adjust the vm.swappiness setting. However, there are a few
reasons we look to control the balance of file vs anon during proactive
reclaim, separately from reactive reclaim:
* Swapout should be limited to manage SSD write endurance. In near-OOM
situations we are fine with lots of swap-out to avoid OOMs. As these
are typically rare events, they have relatively little impact on write
endurance. However, proactive reclaim runs continuously and so its
impact on SSD write endurance is more significant. Therefore it is
desireable to control swap-out for proactive reclaim separately from
reactive reclaim
* Some userspace OOM killers like systemd-oomd[1] support OOM killing on
swap exhaustion. This makes sense if the swap exhaustion is triggered
due to reactive reclaim but less so if it is triggered due to proactive
reclaim (e.g. one could see OOMs when free memory is ample but anon is
just particularly cold). Therefore, it's desireable to have proactive
reclaim reduce or stop swap-out before the threshold at which OOM
killing occurs.
In the case of Meta's Senpai proactive reclaimer, we adjust vm.swappiness
before writes to memory.reclaim[2]. This has been in production for
nearly two years and has addressed our needs to control proactive vs
reactive reclaim behavior but is still not ideal for a number of reasons:
* vm.swappiness is a global setting, adjusting it can race/interfere
with other system administration that wishes to control vm.swappiness.
In our case, we need to disable Senpai before adjusting vm.swappiness.
* vm.swappiness is stateful - so a crash or restart of Senpai can leave
a misconfigured setting. This requires some additional management to
record the "desired" setting and ensure Senpai always adjusts to it.
With this patch, we avoid these downsides of adjusting vm.swappiness
globally.
Previously, this exact interface addition was proposed by Yosry[3]. In
response, Roman proposed instead an interface to specify precise
file/anon/slab reclaim amounts[4]. More recently Huan also proposed this
as well[5] and others similarly questioned if this was the proper
interface.
Previous proposals sought to use this to allow proactive reclaimers to
effectively perform a custom reclaim algorithm by issuing proactive
reclaim with different settings to control file vs anon reclaim (e.g. to
only reclaim anon from some applications). Responses argued that
adjusting swappiness is a poor interface for custom reclaim.
In contrast, I argue in favor of a swappiness setting not as a way to
implement custom reclaim algorithms but rather to bias the balance of anon
vs file due to differences of proactive vs reactive reclaim. In this
context, swappiness is the existing interface for controlling this balance
and this patch simply allows for it to be configured differently for
proactive vs reactive reclaim.
Specifying explicit amounts of anon vs file pages to reclaim feels
inappropriate for this prupose. Proactive reclaimers are un-aware of the
relative age of file vs anon for a cgroup which makes it difficult to
manage proactive reclaim of different memory pools. A proactive reclaimer
would need some amount of anon reclaim attempts separate from the amount
of file reclaim attempts which seems brittle given that it's difficult to
observe the impact.
[1]https://www.freedesktop.org/software/systemd/man/latest/systemd-oomd.service.html
[2]https://github.com/facebookincubator/oomd/blob/main/src/oomd/plugins/Senpai.cpp#L585-L598
[3]https://lore.kernel.org/linux-mm/CAJD7tkbDpyoODveCsnaqBBMZEkDvshXJmNdbk51yKSNgD7aGdg@mail.gmail.com/
[4]https://lore.kernel.org/linux-mm/YoPHtHXzpK51F%2F1Z@carbon/
[5]https://lore.kernel.org/lkml/20231108065818.19932-1-link@vivo.com/
This patch (of 2):
We use the constants 0 and 200 in a few places in the mm code when
referring to the min and max swappiness. This patch adds MIN_SWAPPINESS
and MAX_SWAPPINESS #defines to improve clarity. There are no functional
changes.
Link: https://lkml.kernel.org/r/20240103164841.2800183-1-schatzberg.dan@gmail.com
Link: https://lkml.kernel.org/r/20240103164841.2800183-2-schatzberg.dan@gmail.com
Signed-off-by: Dan Schatzberg <schatzberg.dan@gmail.com>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Chris Li <chrisl@kernel.org>
Reviewed-by: Nhat Pham <nphamcs@gmail.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Tejun Heo <tj@kernel.org>
Cc: Yosry Ahmed <yosryahmed@google.com>
Cc: Yue Zhao <findns94@gmail.com>
Cc: Zefan Li <lizefan.x@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Put legacy cgroup v1 memory controller code under a new CONFIG_MEMCG_V1
config option. The option is turned off by default. Nobody except those
who are still using cgroup v1 should turn it on.
If the option is not set, memory controller can still be mounted under
cgroup v1, but none of memcg-specific control files are present.
Please note, that not all cgroup v1's memory controller code is guarded
yet (but most of it), it's a subject for some follow-up work.
Thanks to Michal Hocko for providing a better Kconfig option description.
[roman.gushchin@linux.dev: better config option description provided by Michal]
Link: https://lkml.kernel.org/r/ZnxXNtvqllc9CDoo@google.com
Link: https://lkml.kernel.org/r/20240625005906.106920-14-roman.gushchin@linux.dev
Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Group all cgroup v1-related declarations at the end of memcontrol.h and
mm/memcontrol-v1.h with an intention to put them all together under a
config option later on. It should make things easier to follow and
maintain too.
Link: https://lkml.kernel.org/r/20240625005906.106920-13-roman.gushchin@linux.dev
Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
memcg1_update_tree() is not used outside of mm/memcontrol-v1.c anymore,
define it as static and remove the declaration from the header file.
Link: https://lkml.kernel.org/r/20240625005906.106920-12-roman.gushchin@linux.dev
Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Rename memcg_oom_recover() into memcg1_oom_recover() for consistency with
other memory cgroup v1-related functions.
Move the declaration in mm/memcontrol-v1.h to be nearby other memcg v1 oom
handling functions.
Link: https://lkml.kernel.org/r/20240625005906.106920-10-roman.gushchin@linux.dev
Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cgroup v1 supports a complicated OOM handling in userspace mechanism,
which is not supported by cgroup v2. Let's move the corresponding code
into memcontrol-v1.c.
Aside from mechanical code movement this patch introduces two new
functions: memcg1_oom_prepare() and memcg1_oom_finish(). Those are
implementing cgroup v1-specific parts of the common memcg OOM handling
path.
Link: https://lkml.kernel.org/r/20240625005906.106920-9-roman.gushchin@linux.dev
Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Rename memcg_check_events() into memcg1_check_events() for consistency
with other cgroup v1-specific functions.
Link: https://lkml.kernel.org/r/20240625005906.106920-8-roman.gushchin@linux.dev
Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cgroup v1's memory controller contains a pretty complicated event
notifications mechanism which is not used on cgroup v2. Let's move the
corresponding code into memcontrol-v1.c.
Please, note, that mem_cgroup_event_ratelimit() remains in memcontrol.c,
otherwise it would require exporting too many details on memcg stats
outside of memcontrol.c.
Link: https://lkml.kernel.org/r/20240625005906.106920-7-roman.gushchin@linux.dev
Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Rename exported function related to the charge move to have the memcg1_
prefix.
Link: https://lkml.kernel.org/r/20240625005906.106920-6-roman.gushchin@linux.dev
Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Unlike the legacy cgroup v1 memory controller, cgroup v2 memory controller
doesn't support moving charged pages between cgroups.
It's a fairly large and complicated code which created a number of
problems in the past. Let's move this code into memcontrol-v1.c. It
shaves off 1k lines from memcontrol.c. It's also another step towards
making the legacy memory controller code optionally compiled.
Link: https://lkml.kernel.org/r/20240625005906.106920-5-roman.gushchin@linux.dev
Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Rename exported function related to the softlimit reclaim to have memcg1_
prefix.
Link: https://lkml.kernel.org/r/20240625005906.106920-4-roman.gushchin@linux.dev
Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Soft limits are cgroup v1-specific and are not supported by cgroup v2, so
let's move the corresponding code into memcontrol-v1.c.
Aside from simple moving the code, this commits introduces a trivial
memcg1_soft_limit_reset() function to reset soft limits and also moves the
global soft limit tree initialization code into a new memcg1_init()
function.
It also moves corresponding declarations shared between memcontrol.c and
memcontrol-v1.c into mm/memcontrol-v1.h.
Link: https://lkml.kernel.org/r/20240625005906.106920-3-roman.gushchin@linux.dev
Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "mm: memcg: separate legacy cgroup v1 code and put under
config option", v2.
Cgroups v2 have been around for a while and many users have fully adopted
them, so they never use cgroups v1 features and functionality. Yet they
have to "pay" for the cgroup v1 support anyway:
1) the kernel binary contains an unused cgroup v1 code,
2) some code paths have additional checks which are not needed,
3) some common structures like task_struct and mem_cgroup contain unused
cgroup v1-specific members.
Cgroup v1's memory controller has a number of features that are not
supported by cgroup v2 and their implementation is pretty much self
contained. Most notably, these features are: soft limit reclaim, oom
handling in userspace, complicated event notification system, charge
migration. Cgroup v1-specific code in memcontrol.c is close to 4k lines
in size and it's intervened with generic and cgroup v2-specific code.
It's a burden on developers and maintainers.
This patchset aims to solve these problems by:
1) moving cgroup v1-specific memcg code to the new mm/memcontrol-v1.c file,
2) putting definitions shared by memcontrol.c and memcontrol-v1.c into the
mm/memcontrol-v1.h header,
3) introducing the CONFIG_MEMCG_V1 config option, turned off by default,
4) making memcontrol-v1.c to compile only if CONFIG_MEMCG_V1 is set.
If CONFIG_MEMCG_V1 is not set, cgroup v1 memory controller is still available
for mounting, however no memory-specific control knobs are present.
This patch (of 14):
This patch introduces the mm/memcontrol-v1.c source file which will be
used for all legacy (cgroup v1) memory cgroup code. It also introduces
mm/memcontrol-v1.h to keep declarations shared between mm/memcontrol.c and
mm/memcontrol-v1.c.
As of now, let's compile it if CONFIG_MEMCG is set, similar to
mm/memcontrol.c. Later on it can be switched to use a separate config
option, so that the legacy code won't be compiled if not required.
Link: https://lkml.kernel.org/r/20240625005906.106920-1-roman.gushchin@linux.dev
Link: https://lkml.kernel.org/r/20240625005906.106920-2-roman.gushchin@linux.dev
Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
